{"id":"F2006B02158","name":"AD/AC/97 - Aircraft Flight Manual, Flight into Icing Conditions","slug":"ad-ac-97-aircraft-flight-manual-flight-into-icing-conditions","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41388,"registerId":"commonwealth-F2006B02158-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.","sortOrder":0},{"sectionNumber":"AD/AC/97 Aircraft Flight Manual, Flight ","sectionType":"part","heading":"AD/AC/97 Aircraft Flight Manual, Flight into Icing Conditions 3/2000","content":"# AD/AC/97 Aircraft Flight Manual, Flight into Icing Conditions 3/2000\n\nApplicability: Models 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680FL(P), 680T, 680V, 680W, 681, 685, 690, 690A, 690B, 690C, 690D, 695, 695A,\n\n695B, and 720, all serial numbers.\n\nRequirement: Revise:\n\n    the Limitations Section of the aircraft's Aircraft Flight Manual (AFM) by incorporating the following:","sortOrder":1},{"sectionNumber":"\"WARNING\"","sectionType":"part","heading":"\"WARNING\"","content":"# \"WARNING\"\n\nSevere icing may result from environmental conditions outside of those for which the aircraft is certificated.\n\nFlight in freezing rain, freezing drizzle, or mixed icing conditions (super cooled liquid water and ice crystals) may result in:\n\n    ice build-up on protected surfaces and exceed the capability of the ice protection system, or\n\n    ice forming aft of the protected surfaces.\n\nThis ice may not be shed using the ice protection systems, and may seriously degrade the performance and controllability of the aircraft.","sortOrder":2},{"sectionNumber":"THE FOLLOWING WEATHER CONDITIONS MAY BE ","sectionType":"part","heading":"THE FOLLOWING WEATHER CONDITIONS MAY BE CONDUCIVE TO SEVERE IN-FLIGHT ICING:","content":"# THE FOLLOWING WEATHER CONDITIONS MAY BE CONDUCIVE TO SEVERE IN-FLIGHT ICING:\n\n    Visible rain at temperatures below 0 degrees Celsius ambient air temperature;\n    Droplets that splash or splatter on impact at temperatures below 0 degrees Celsius ambient air temperature.","sortOrder":3},{"sectionNumber":"PROCEDURES FOR EXITING A SEVERE ICING","sectionType":"part","heading":"PROCEDURES FOR EXITING A SEVERE ICING","content":"# PROCEDURES FOR EXITING A SEVERE ICING\n\nENVIRONMENT: (These procedures are applicable to all flight phases from take-off to landing.)\n\nMonitor the ambient air temperature.","sortOrder":4}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD remains tightly focused on its original purpose: addressing a specific unsafe icing condition in specific Aero Commander aircraft models. The scope has not expanded beyond the original safety concern."},"complexity_factors":["Very short document (approximately 300 words)","Only 1 defined term (AFM - Aircraft Flight Manual)","No cross-references to other legislation or regulations beyond the enabling power (CAR 1998 subregulation 39.1(1))","Simple conditional structure: if you operate these aircraft models, you must insert this text into your manual","No nested exceptions or complex logical operators","Single, clear compliance action with no alternative methods or phased implementation"],"plain_english_summary":"This CASA Airworthiness Directive mandates that owners/operators of specified Aero Commander 500–720 series aircraft update their Aircraft Flight Manual with a prominent warning about severe icing. It stresses recognition of freezing rain/drizzle and mixed‑ice conditions and requires immediate exit procedures, because real‑world icing can exceed certification limits and render the airplane uncontrollable. The AD applies to private owners, operators, schools and maintenance organizations of the listed models."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD is narrowly focused: it requires incorporation of specific warning and exiting procedures into the AFM for the listed aircraft. Based on the text provided, it does not broaden the regulatory reach beyond that original safety-focused purpose (i.e. it does not mandate hardware modifications, inspections, or operational bans). The instrument therefore appears to remain within its original, narrowly safety-directed scope."},"complexity_factors":["Single, focused requirement: revise AFM Limitations section with prescribed text","Long applicability list: ~30 aircraft model variants listed (increases reading and identification work for operators)","Minimal cross‑referencing: only a single regulatory source cited (CAR 1998 subreg 39.1(1))","No nested exceptions or conditional logic in the AD text provided","Implementation dependency: effectiveness depends on operator training and operational policy (adds practical complexity not present in the text)","Incomplete excerpt: compliance timing not shown in the provided text (raises practical ambiguity)"],"plain_english_summary":"**What this instrument does (mechanically)\n\n- Requires operators/owners of a specified list of aircraft models to revise the Limitations section of their Aircraft Flight Manual (AFM). The required text is a warning about \"severe icing\" and specific procedures for exiting severe icing conditions (see \"Requirement\" and \"Procedures for exiting a severe icing environment\").\n\n- The mandate is issued as an Airworthiness Directive under subregulation 39.1(1) of the Civil Aviation Regulations 1998 (the CASA delegate signs and issues the AD). The AD names the affected aircraft models (Applicability) and specifies the text that must be included in the AFM (Requirement).\n\nWho is affected\n\n- Directly affected: owners, operators and maintenance organisations responsible for the listed aircraft models (Models 500, 500A, 500B, 500S, 500U, 520, 560, 560A, 560E, 560F, 680, 680E, 680FL(P), 680T, 680V, 680W, 681, 685, 690, 690A, 690B, 690C, 690D, 695, 695A, 695B, and 720, all serial numbers).\n\n- Indirectly affected: pilots flying those aircraft (through the AFM content they must follow), insurers and air operators who rely on AFM content to set procedures and training.\n\nWhy it matters (purpose claims and practical effects)\n\n- The AD's stated safety purpose is to ensure AFMs warn about \"severe icing\" conditions (notably freezing rain, freezing drizzle, and mixed icing) and include procedures to exit such conditions. That is intended to reduce risk from ice accumulation beyond the capability of existing ice-protection systems (Requirement; Warning text).\n\n- Practical effects: AFMs will formally record the hazard and required pilot behaviour. This changes the information available to pilots and operators and can affect operational decisions (flight planning, dispatch, in‑flight deviations), pilot training, and standard operating procedures.\n\nHow it affects costs, incentives and behaviour\n\n- Who pays: operators/owners pay the administrative cost of amending the AFM, updating training materials and pilot briefings, and any downstream operational costs (flight delays, diversions, or rerouting to avoid the conditions described).\n\n- Who decides: the CASA delegate issues the AD; operators must implement the AFM text. Pilots/operators retain operational discretion but will be constrained by the AFM instructions and by any operator procedures that incorporate the AFM wording.\n\n- Behavioural change: the AD makes the risk explicit and prescribes monitoring ambient air temperature and exiting severe icing conditions, which tends to encourage avoidance of freezing rain/freezing drizzle and prompt exit procedures if those conditions are encountered. That can increase safety margins but may increase flight cancellations, diversions, or route planning costs.\n\nTrade‑offs, implementation risks and compliance burden\n\n- Trade-offs: the measure trades operational flexibility and potential economic efficiency (possible additional diversions, delays, or cancelled flights) for reduced risk of loss of control or performance degradation due to severe icing.\n\n- Compliance burden: largely administrative (updating AFM text) plus training to ensure pilots follow the new AFM wording. The AD does not itself require equipment changes, inspections or recurring ground works in the text provided.\n\n- Implementation risk: effective risk reduction depends on operators actually training crews and applying AFM procedures in operational decisions. The AD relies on AFM revision and pilot adherence rather than technical modification of the aircraft.\n\nPossible second‑order effects\n\n- Insurance and liability: formal AFM warnings can change expectations about standards of care and operating limits; insurers and courts may refer to AFM content when assessing operational decisions.\n\n- Substitution effects: some operators may elect to avoid operating in forecast icing conditions or move to different aircraft types for affected routes, increasing operational costs for those operators.\n\nConcentrated benefits and diffuse costs\n\n- Concentrated benefits accrue to operators and crews who avoid accidents and to manufacturers/operators in reduced accident‑related costs.\n\n- Costs are diffuse across affected operators in the form of minor administrative updates, training, and potential operational impacts.\n\nSource mechanics and enforcement\n\n- The AD is issued under CAR 1998 subregulation 39.1(1) by a CASA delegate; compliance is mandatory for the aircraft named in the Applicability section. The Requirement section specifies the exact AFM wording to be incorporated.\n\n(References: Applicability; Requirement; Warning; Procedures for exiting a severe icing environment.)"},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-ac-97-aircraft-flight-manual-flight-into-icing-conditions","history":"/api/acts/ad-ac-97-aircraft-flight-manual-flight-into-icing-conditions/history","analysis":"/api/acts/ad-ac-97-aircraft-flight-manual-flight-into-icing-conditions/analysis","conflicts":"/api/acts/ad-ac-97-aircraft-flight-manual-flight-into-icing-conditions/conflicts","importantCases":"/api/acts/ad-ac-97-aircraft-flight-manual-flight-into-icing-conditions/important-cases","documents":"/api/acts/ad-ac-97-aircraft-flight-manual-flight-into-icing-conditions/documents"}}